Which method allows you to have common extensions visible when viewing the files?

To have common file extensions visible when viewing files, you can enable the option to show file extensions in your operating system's settings. For example, in Windows, you can go to File Explorer, click on the "View" tab, and check the box for "File name extensions." On macOS, you can go to Finder, select "Preferences," then check "Show all filename extensions." This will allow you to see the extensions for all files in the file manager.